In the field of electronics technology, the processing capability of a CPU (Central Processing Unit) is one of the most important factors to affect the performance of an electronic device. With the improvement of CPU manufacturing techniques, multiprocessor technology has seen increasing applications in more and more electronic devices so as to satisfy multitask requirements.
In existing multiprocessor systems, a processor, such as a CPU, and its peripheral basic circuits, are generally designed as a relatively independent CPU module. Through board-to-board connectors, a plurality of such CPU modules are connected to a baseboard respectively, to form a multiprocessor system. On the baseboard, corresponding peripheral equipments can be mounted according to various requirements. Since the baseboard and each of the CPU modules can be upgraded separately, cost may be reduced greatly during upgrade process of the multiprocessor system.
FIG. 1 shows the top view of a conventional multiprocessor system. As shown in FIG. 1, a plurality of CPU modules, namely CPU module 1# and CPU module 2#, are laid onto baseboard 0# via board-to-board connectors 10 and 20 respectively. CPU 1# and CPU 2# which are mounted on the CPU module 1# and CPU module 2#, communicate with peripheral equipments mounted on the baseboard 0# through a Peripheral Component Interconnect (PCI) bus. FIG. 2 is the front view of the conventional multiprocessor system.
However, at the very beginning of designing a multiprocessor system formed in a tiled fashion, it is generally difficult to predict functions potentially to be added in the future. Accordingly, if the reserved CPU modules are far more than actual requirements, it will lead to increase in the cost of the multiprocessor system; and on the other hand, if the reserved CPU modules are not sufficient, the extensibility of the multiprocessor system will be limited by the finite space constraints.
Moreover, in existing multiprocessor systems, the configuration of each CPU module must be varied to process unsymmetrical signals. Here, the configuration of a CPU module comprises the fabrication process of the CPU module, the Printed Circuit Board (PCB) and the components incorporated therein; and the unsymmetrical signals comprise request/reply signals, interrupt signals, clock signals, initialization device select signals and reset signals. Accordingly, this will also increase the costs for manufacturing and maintaining the multiprocessor system.